Our short-term objective is the development of algorithms for locating, enhancing, and recognizing selected classes of objects in radiographic images. Our long term objective is the development of a computer-based technology for assisting the physician in the diagnosis of medical images, particularly radiographs, ultrasonic scans, and isotope scans. Included within this objective are the detection, acquisition, analysis, storage, and transmission of medical images at high speed, high resolution and low doses of radiant energy. To achieve these objectives we shall build upon the results of our research over the past several years on medical applications of computer-aided image processing and pattern recognition. Our plan of research consists of six concurrent Units: 1) image filtering, 2) edge and surface detection, 3) texture analysis, 4) three-dimensional modeling, 5) mammography, and 6) a command language for chest radiography. All of these Units are oriented toward the development of computer-aided techniques for analyzing medical images. Although the emphasis of this research is directed toward radiology, the techniques and insights developed in this project are applicable to a much wider class of medical images, including isotope scans and ultrasonic images.